The effect of temperature on hatch and activity of second-stage juveniles of the root-knot nematode, Meloidogyne minor, an emerging pest in north-west Europe

Abstract

Abstract Meloidogyne minor is a serious threat to turfgrass in north-west Europe, and has a broad host range that includes other economically important plants. The species was described only recently and little is known about its biology. This study examines the effect of temperature on hatch and motility of second-stage juveniles (J2), and records hatching from egg masses collected from golf greens in different seasons. Eggs were present throughout the year and a high percentage hatch (46-88%) was recorded when they were incubated at 20°C. When egg masses were incubated at constant temperatures, J2 hatched between 15 and 25°C, with limited hatch (<1%) at 10 and 30°C. The percentage hatch was lower at 15°C (43%) than at 20-25°C (63-76%). J2 hatched fastest at 23°C, with an average duration to hatching of 7 days compared to 17 days at 15°C. The range of temperatures at which J2 was active was broader than that at which they hatched. J2 were active from 4-30°C, with greatest activity between 15 and 25°C. The addition of grass root extract temporarily increased J2 activity at 10-20°C, but not at lower temperatures.